The present invention relates to improved dental tapes. Specifically, the improved dental tapes of the present invention contain substantially crystal-free coatings that: (a) comprise from 20 to 120% by weight of the floss filament, (b) are saliva soluble and (c) exhibit a minimum of flaking. Yet these coatings are released in total into the oral cavity during flossing and can contain ingredients such as abrasives that work with the tape to help physically remove biofilms from interproximal and subgingival surfaces, and chemotherapeutic ingredients affecting oral health and subsequent systemic diseases caused or exacerbated by poor oral health. These coatings are particularly adapted to monofilament dental tapes.
Historically the purpose of dental floss was: (1) to dislodge and remove decomposing food material that accumulated at interproximal and subgingival surfaces and could not be removed by brushing or rinsing, and (2) to dislodge and remove bacteria, plaque and/or calculus that accumulated since the previous flossing and/or cleaning.
The concept of the use of dental floss for cleansing interproximal spaces appears to have been introduced by Parmly in 1819. Parmly suggested the use of waxed silk to clean teeth of persons subject to gingival inflammation.
The role of plaque, now described as subgingival biofilm, in gum disease is well documented. The need to physically remove subgingival biofilms routinely has become an accepted treatment for gum disease. Mechanical removal of subgingival biofilms can be achieved professionally through: scaling, planing, prophylaxis and polishing, and individually by tooth brushing, proxy brushing and flossing.
While these methods of physically removing subgingival biofilms from tooth surfaces are effective and well accepted; gum disease continues to be prevalent in the adult population, and consequently, improved means for the individual to physically remove subgingival biofilms routinely are indicated.
Furthermore, the spacing between teeth is not uniform and it varies considerably, not only from one place to another between the same pair of teeth, but also from one pair of teeth to another pair of teeth. The spacing varies in the same individual, among different individuals, and especially in the case of twisted teeth and teeth that have fillings, crowns, etc.
To accommodate tight spacing and those interproximal contacts that do not allow multifilament dental floss to be worked between teeth without fraying, breaking, etc., a vast array of xe2x80x9cTEFLONxe2x80x9d dental flosses have been commercialized. These shred-resistant, monofilament tapes are described in detail in the following U.S. patents, which are hereby incorporated by reference: U.S. Pat. Nos. 3,664,915; 3,953,566; 3,962,153; 4,096,227; 4,187,390; 4,256,806; 4,385,093; 4,478,665; 4,776,358; 5,033,488; 5,209,251; 5,220,932; 5,518,012; 5,718,251; 5,765,576; and 5,911,228.
The TEFLON-type tapes available commercially in the marketplace today, include: Gore""s Glide(copyright), Oral-Bs Satin Floss(copyright), Johnson and Johnson""s Easy Slide(copyright), and Colgate""s Total(copyright)). All of these tapes can be worked between tight spaces with a minimum of fraying and breaking. Yet, unlike their multifilament counterparts such as Johnson and Johnson""s woven floss, REACH(copyright)Gentle Gum Care, during flossing, these tapes do not release substantial quantities of cleaners, abrasives, tartar control ingredients, whiteners and active ingredients such as fluoride, antimicrobials, antibiotics, etc. The net of this shorting in failing to deliver substantial quantities of ingredients to those sites being flossed is that the tapes are generally perceived as most convenient fitting between teeth, but unfortunately, they are generally perceived as: xe2x80x9cnot cleaningxe2x80x9d, xe2x80x9cnot workingxe2x80x9d, xe2x80x9cnot doing muchxe2x80x9d, etc., once they are positioned between teeth.
When substantial quantities of cleaning, conditioning and treating substances are coated onto tapes, the resultant tapes are characterized by excessive flaking and breaking off of these coatings during processing, dispensing and wrapping of tape around the fingers. As a result, there are no commercial tapes available with substantial coatings of releasable ingredients suitable for working into and physically removing biofilms from interproximal and subgingival spaces.
Biofilms are notorious throughout nature for being difficult to remove. Working a monofilament tape over biofilms in the absence of substantial quantities of cleaners, abrasives, etc., is not effective in physically removing and/or disrupting substantial quantities of biofilms. The net is, critical biofilm buildup interproximally and subgingivally cannot be effectively physically removed with routine flossing with current commercial dental tapes, both PTFE tapes and bicomponent tapes.
Monofilament interproximal devices are described and claimed in: U.S. Pat. Nos. Re 35,439; 3,800,812; 4,974,615; 5,760,117; 5,433,226; 5,479,952; 5,503,842; 5,755,243; 5,845,652; 5,884,639; 5,918,609; 5,962,572; 5,998,431; 6,003,525; 6,083,208; 6,148,830; 6,161,555; and 6,027,592, the disclosures of which are hereby incorporated herein by reference. These dental tapes generally have serious shortcomings in gentleness, in delivering coatings during flossing and in being handled easily and conveniently during flossing.
Polytetrafluoroethylene (PTFE) based interproximal devices are described in: U.S. Pat. Nos. 5,209,251; 5,033,488; 5,518,012; 5,911,228; 5,220,932; 4,776,358; 5,718,251; 5,848,600; 5,787,758; and 5,765,576. To date, no commercial versions of these tapes have been coated effectively and cannot be used to deliver active ingredients, interproximally and subgingivally during flossing. Handling during flossing is difficult. Most have to provide a consumer acceptable edge. Many are plagued with serious dimensional inconsistency problems, as well.
Several patent applications have been filed on monofilament dental tapes with coatings comprising from between about 20% by weight and about 120% by weight of the monofilament tape. These are described in copending U.S. Provisional Patent Application Serial Nos. 60/227,433 and 60/227,255, filed Aug. 23, 2000 and Ser. No. 60/263,220, filed Jan. 22, 2001, all of which are hereby incorporated by reference.
There is clearly a need for a commercial, shred-resistant tape that is coated with releasable ingredients that help disrupt and/or physically remove biofilms from critical interproximal and subgingival sites when used regularly, and deliver chemotherapeutic agents as required in a site-specific manner.
The present invention centers around the observation that the substantivity of coatings onto flexible surfaces, including dental tapes, can be enhanced such that during flexure of the surface, these enhanced coatings remain substantive to said surface and resist cracking, fracturing and flaking off. Specifically, it has been observed that most coated flexible surfaces, especially those formulated to be saliva-soluble and carry effective quantities of abrasives, cleaners, surfactants, and chemotherapeutic agents, fracture along crystal faces during flexure, thereafter releasing the ingredients from the flexible surface by cracking, chipping, flaking and/or falling off etc. In response to these observations, it has been unexpectedly found that the addition of certain substances to various coatings at relatively modest levels reduces crystal formation while simultaneously enhancing the coating""s substantivity to flexible surfaces subjected to flexure, which properties thereby impart outstanding flake resistance and release value to said tape.
Those coating additives that reduce, control and/or eliminate crystal formation and enhance the substantivity of the coating to flexible surfaces when added to these coatings at modest levels include certain aliphatic, long chain, fatty alcohols having from between about 10 and 30 carbon atoms and/or various liquid surfactants such as polyethylene glycol sorbitan dialiphatic esters.
Suitable aliphatic, long chain, fatty alcohols for the crystal-free coatings of the present invention can be represented by the structural formula ROH, wherein R represents a long chain alkyl group having from 20 to 30 carbon atoms. Specific examples include:
Naturally occurring mixtures with substantial quantifies of these fatty alcohols, or isomers thereof; including those chemically derived from natural sources also constitute suitable sources of aliphatic, long chain fatty alcohols for the purpose of this invention.
The long chain fatty alcohols can be represented by the structural formula ROH wherein R represents a long chain alkyl group having from 10 to 30 carbon atoms. These can be purchased commercially from Stepan, Proctor and Gamble and Aldrich Chemical Co. and a variety of companies processing vegetable and animal derived fatty alcohols.
Suitable liquid surfactants for the crystal-free coatings of the present invention include polyoxyethylene glycol sorbitan mono- and di-aliphatic esters represented by the general formula: 
wherein R1, R2, R3, R4 are H or aliphatic acyl groups from (10 to 30) and the sum of w, x, y, and z is from between 20 and 80. These liquid surfactants are available under the trade names Emsorb(copyright), Span(copyright), Tween(copyright) from Cognis N.A. and ICI. Specific examples of these include:
PEG 20 sorbitan monooleate (Tween(copyright) 80, ICI);
PEG 40 sorbitan monostearate (Span 60(copyright), ICI); and
PEG 40 sorbitan diisostearate (Emsorb(copyright) 2726, Cognis, N.A.).
Similar esterified, PEG-based surfactants, which are known to those having ordinary skilled in the art, are also suitable liquid surfactants.
One preferred embodiment of this invention thus comprises substantive coatings for flexible surfaces that, under flexure, resist cracking, flaking, breaking off, etc.
Another preferred embodiment of the present invention comprises a shred-resistant dental tape that physically removes biofilms from interproximal and subgingival sites.
Another preferred embodiment of the invention comprises a method of applying substantive coatings of biofilm disrupting substances to shred-resistant tapes which coatings are released onto and worked into biofilms during flossing.
A further preferred embodiment of the invention comprises shred-resistant tapes with substantive coatings that exhibit minimum flaking, yet achieve total release during flossing.
Yet another preferred embodiment of the invention comprises monofilament tapes with substantially crystal-free coatings that are substantive, saliva soluble and exhibit with a minimum of flaking.
Still another preferred embodiment of the invention comprises a shred-resistant dental tape with a substantive coating that helps physically remove biofilms when released from the tape during flossing.
A further preferred embodiment of the present invention comprises substantive coatings for dental tapes that contain biofilm disrupting and physically removing ingredients along with biologically active or chemotherapeutic ingredients, all of which are largely or totally released during flossing.
Still another preferred embodiment of the present invention comprises a method for treating interproximal and subgingival sites to remove subgingival and interproximal biofilms while treating said sites with active ingredients.
Yet another preferred embodiment of the invention comprises a method for manufacturing a shred-resistant dental tape that contains substantial levels of biofilm disrupting/removing ingredients that do not flake off; yet are totally releasable during flossing.
Another preferred embodiment of the invention comprises coated dental tapes with a flaking value of less than about 20.
A further preferred embodiment of the invention comprises a class of coated dental tapes with coating release values approaching about 100.
These and other embodiments of the invention are described in detail below.